For today's complex cellular networks, traffic control has become essential for efficient utilization of the overall available resources.
Nowadays, the world of cellular communication is characterized by simultaneous deployment of multiple Radio Access Technologies (RATs) and multiple bands of the same RATs in a given coverage area of a given operator. Multi-RAT and multi-band cellular communication environment can result from implementing emerging new cellular communication standards whilst retaining legacy technologies for as long as possible. Such environment can be also caused by fragmented spectrum received for a given RAT by a given operator due to licensing issues and for other reasons.
Mobile operators face a growing need to define how and when their network resources are used, and to balance the load of respective network resources. Efficient utilization of the available pool of resources requires traffic control aiming at distributing the load in an optimal manner. Distributing the load may be performed between different cells by handing over transmission of data to other cells at a same frequency and/or across different RATs and bands.
Problems of controlling traffic in cellular networks have been recognized in the conventional art and various techniques have been developed to provide solutions. For example:
US Patent Application No. 2009/0323530 discloses a method, program, system and apparatus performing dynamic load balancing of coverage areas in a wireless communication network. Dynamic load balancing is performed by evaluating cell congestion based on location information of subscribers in the wireless communication network, collecting network parameters related to the wireless communication network and altering network parameters based on the evaluated cell congestion. After the network parameter is altered, the coverage areas are narrowed. Improvements in cell congestion and quality of server are then determined based on the narrowing of the coverage areas. Altering the plurality of network parameters and evaluating cell congestion are performed continuously until a target quality of service is achieved.
US Patent Application No. 2011/0039564 discloses a method of operation of a cellular access point amongst a plurality of interconnected cellular access points, the method comprising: receiving from a first user equipment a connection attempt that would cause the access point to exceed a first predetermined capacity threshold; selecting one of the previously connected user equipments and an associated one of the plurality of interconnected cellular access points; initiating a handover of the selected one of the previously connected user equipments to the associated one of the plurality of interconnected cellular access points; and establishing a connection with the first user equipment.
US Patent Application No. 2011/0222416 discloses systems and methods for facilitating inter-cell interference coordination using load indication. A UE may receive load indicator signals from a plurality of base stations in adjacent cells and determine, based at least in part on the load indicator signals, a transmit power metric. The transmit power metric may be provided to a serving base station, which may allocate uplink resources based on the transmit power metric. Additional information related to receiver sensitivity and/or path loss may be used to determine the transmit power metric.
US Patent Application No. 2013/0077491 discloses a method of controlling network traffic via a traffic detection function at the user equipment. The method includes obtaining, at an electronic device, an application configuration, the application configuration including an application identifier identifying an application of a plurality of applications and a network communication characteristic corresponding to each of the plurality of applications. The method further includes detecting, at the electronic device, the application identifier in a packet of network traffic. The method also includes transmitting, from the electronic device, the packet of network traffic based on the network communication characteristic corresponding to the detected application identifier. By providing an application identifier, fine grained (e.g., application specific) network controls may be implemented such as quality of service, charging/accounting, idle handoff, and traffic redirection/load balancing.
International Patent Application No. WO10/133256 discloses a technique when a load of an apparatus of a communications network is evaluated and handover parameters to be advertised for mobile station decided handover are adapted accordingly. Radio resource management information may be exchanged between the apparatus and at least one neighboring apparatus in the communications network, and a load of the at least one neighboring apparatus may be evaluated from the exchanged radio resource management information. The handover parameters to be advertised may be adapted in case the evaluated load of the apparatus and the evaluated load of the at least one neighboring apparatus have reached predetermined limits. Mobile stations of a communications network system are provided with modified handover parameters which induce the mobile stations to make a handover decision as desired by a network infrastructure.
International Patent Application No. WO13/156067 discloses a method for configuring a handover procedure of user equipment from a source cell to a target cell within a cellular network system. The cellular network system comprises the source cell and at least one neighboring target cell. The handover procedure is based on measurements being performed by the user equipment prior to a handover, wherein the measurements are based on a cell individual offset. A cell individual offset is assigned to each of the at least one neighboring target cell in relation to the source cell, wherein the cell individual offset is adaptable by a mobility robustness optimization algorithm and a mobility load balancing algorithm. The method comprises computing a first value for the cell individual offset for each of the at least one neighboring target cell representing an optimum cell individual offset for the mobility robustness optimization algorithm, computing a second value lower than or equal to the first value and a third value higher than or equal to the first value for the cell individual offset for each of the at least one neighboring target cell, the second value representing the lowest value being acceptable for the mobility robustness optimization algorithm and the third value representing the highest value being acceptable for the mobility robustness optimization algorithm, setting the cell individual offset to the first value by the mobility robustness optimization algorithm, adapting the cell individual offset between the second value and the third value by the mobility load balancing algorithm, and configuring a handover procedure for the user equipment from the source cell to a target cell based on user equipment measurements being based on the adapted cell individual offset.
International Patent Application No. WO13/167187 discloses a method for resetting mobility parameters being associated with a handover procedure for a user equipment between a source cell and a target cell within a cellular network system. The cellular network system comprises the source cell and at least one neighboring target cell, wherein the handover procedure is initiated by a trigger value, wherein a trigger value is assigned to each of the at least one neighboring target cell in relation to the source cell, wherein the trigger value is dependent on mobility parameters being adaptable by a mobility robustness optimization algorithm and is dependent on mobility parameters being adaptable by a mobility load balancing algorithm. The method comprises resetting the mobility parameters for the mobility robustness optimization algorithm or the mobility load balancing algorithm, generating a message comprising information about the reset of the mobility parameters being associated with the mobility robustness optimization algorithm or the mobility load balancing algorithm and comprising information about the associated algorithm, and transmitting the message between the source cell and the at least one neighboring cell for resetting the mobility parameters of the associated algorithm based on the received message.
International Patent Application No. WO14/016280 discloses a method for implementing a cell load balancing mechanism in wireless networks. The method comprises at least one wireless user terminal (UE) connected through a wireless network to a serving base station and a plurality of network cells, each one comprising at least a base station and/or radio network controllers, each network cell broadcasting a cell load indicator. The at least one wireless user terminal performs following actions: collecting said broadcasted cell load indicator of each one of said plurality of network cells, providing to the wireless network, information about the actual cell load indicators of the plurality of cells, and performing a network cell selection based on the broadcasted cell load indicators, wherein the cell selection is performed without any exchange of cell load indicators between the plurality of network cells.